In their most familiar form, rotary cutting tools of the type disclosed in the instant application are known in the trade as backspot-facing tools, although with slight modification, the tool could be made to operate as an internal reaming device merely by changing the cutting edges to the outer periphery. Basically, the tools of this nature have taken two distinct forms; one form responsive to rearward and forward rotation of the spindle causes a cutter to extend outwardly by centrifugal force and perform a cutting operation, as seen for example in the Johansson patent, U.S. Pat. No. 3,540,324. In addition, there have been positively actuated cutters which move inwardly and outwardly in response to reciprocal movement of an actuating rod and are connected to an air motor as for example, seen in the MacDonald patent, U.S. Pat. No. 3,572,182. Other more simplified forms utilizing the principle of engagement of a stop collar are seen, as for example, in the Winberry U.S. Pat. No. 3,008,360. One of the problems presented by some of the tools of the prior art is that they do not adapt themselves well to automated maching operations and quick change tool holders or have the ability to be properly programmed into an automated operation.